The song Cassidy is singing to the baby in the opening scene is his own version of "Charlotte the Harlot".
When Tulip purchases a new refrigerator, she is seen putting food back into the fridge, including plasma packs into the freezer. It is also evident that the plasma is in a liquid state and not frozen. While health care facilities are not allowed to refreeze plasma, scientific study has shown that there is a negligible effect on coagulation, and it therefore should not matter. DNA however, can degrade thru refreezing and thawing cycles. Vampires, on the other hand, are only interested in the blood's hemoglobin, which is not affected by refreezing, whatsoever.